Extendable Fence

ABSTRACT

An extendable fence is an underground fence barrier which prevents dogs from digging out underneath a fence and escaping the yard. The barrier is supported over the ground surface and includes a horizontal barrier strip with openings. Stakes are inserted trough the openings in the barrier strip and into the ground. The barrier strip extends the length of the fence section that is to be protected. The stakes are close enough together and sufficiently deep enough in the ground to provide an effective barrier under an existing fence. Also, the stakes are vertically adjustable to provide an effective barrier above the ground on uneven terrain whereby there is a gap between the fence bottom and the ground surface.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTINGCOMPACT DISK APPENDIX

Not Applicable

BACKGROUND OF THE INVENTION

The present invention relates to fences and particularly to undergroundfence barrier devices and a method of constructing a device forpreventing dogs from digging under the bottom of a fence and escapingthe yard.

There are various methods that homeowners use to prevent their dog fromdigging out underneath the fence. Often homeowners will dig down below aportion of the fence and insert a board to discourage such digging. Thedog often then goes to another area of the fence or digs the board outof the ground. The homeowner often buried chicken wire, wire mesh, largerocks, or chain links under the fence. Some homeowners have even burieda portion of the fence below the soil surface. However, in addition torequiring excessive soil excavation, these methods can injure the dog.Still another approach has been to incorporate a trench filled withconcrete under the fence. This approach, however, is expensive and maynot be practical in situations where the homeowner has already built thefence, and installation of the trench and concrete would meandismantling the existing fence and rebuilding the fence once theconcrete filled trench is in place. Some prior art devices provide agroup of rods in the openings at the bottom of the fence to anchor thefence section to the ground and to create a barrier in the ground toprevent dogs from digging under the fence section. However, thesedevices require physical attachment to the fence. Furthermore, thesedevices are not satisfactory in situations where there are small gapsbetween the bottom of the fence section and the ground line that ispresent on uneven terrain. Therefore, a review of known devices revealsthat there remains a need for a simple device that does not requirephysical attachment to the fence, is satisfactory on uneven terrain, andprevents dogs from digging out underneath the fence.

BRIEF SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an undergroundfence barrier which prevents dogs from digging out underneath a fenceand escaping the yard. It is another object of the present invention toprovide a method for constructing an underground fence barrier whichprevents dogs from digging out underneath a fence. The underground fencebarrier is supported over the ground surface and includes a horizontalbarrier strip which extends the length of the fence section that is tobe protected. A plurality of stakes or rods are affixed to thehorizontal barrier strip, each stake being vertically oriented. Thebarrier strip includes a plurality of equidistant openings such that astake is inserted through each of the openings and the lower point ofeach stake is driven below the ground surface. The openings are cut tomatch the shape of the stakes such that the openings serve as key holeswhich are dimensioned just slightly smaller than the stakes. Therefore,there is a tight fit between the key holes and the stakes so that thestakes can be driven completely to ground level or partially driven toalso protect any open space between the fence bottom and ground level.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings in which like reference numbers representcorresponding parts throughout:

FIG. 1 is a front view of the underground fence barrier according to apreferred embodiment of the present invention showing stakes drivensequentially through a barrier strip.

FIG. 2 is a plan view of the horizontal barrier strip according to apreferred embodiment of the present invention after the stakes aredriven through the strip.

FIG. 3 is a side view of a typical stake according to a preferredembodiment of the present invention.

FIG. 4 is a front view of the underground fence barrier according to apreferred embodiment of the present invention showing stakes with alarger striking surface being driven sequentially through the barrierstrip.

FIG. 5 is a plan view of the horizontal barrier strip according to apreferred embodiment of the present invention after the stakes with alarger striking surface are driven through the strip.

FIG. 6 is a side view of a stake with a larger striking surfaceaccording to a preferred embodiment of the present invention.

FIG. 7 is a side view of a stake with string clips according to apreferred embodiment of the present invention.

FIG. 8 is a side view of the barrier strip along side an existing fenceon level terrain affixed with stakes oriented in variable verticalpositions showing the stakes driven sequentially through the barrierstrip and into the ground.

FIG. 9 is a prospective view of the barrier strip along side an existingfence affixed with stakes provided with a larger striking surfaceaccording to a preferred embodiment of the present invention.

FIG. 10 is a front view of the barrier strip along side an existingfence on uneven terrain affixed with stakes oriented in variablevertical positions to protect the gap between the bottom of the existingfence and ground surface.

DETAILED DESCRIPTION OF THE INVENTION

It will be readily understood that the components of the embodiments asgenerally described and illustrated in the drawings herein, could bearranged and designed in a wide variety of different configurations.Thus, the following more detailed description of the embodiments of thesystem, components and method of constructing the present invention, asrepresented in the drawings, is not intended to limit the scope of theinvention, as claimed, but is merely representative of the embodimentsof the invention.

Referring now to FIGS. 1 through 10 of the drawings, there is shown anunderground fence barrier, which is constructed in accordance with anembodiment of the present invention and is generally indicated at 10. Asshown in FIGS. 1, 2, 4, and 5 the underground fence barrier 10 includesa plurality of barrier strips 50 and a plurality of stakes 20.

As shown in FIG. 2. the barrier strip 50 may be in the form of alongitudinal half pipe or half cylinder sections because plastic pipe isreadily available and easy to cut. However, the barrier strip 50 couldalso be flat or any other suitable shape. Since the barrier strip 50 maybe provided in sections, the barrier strip 50 may be attached in seriesto another barrier strip 50 to form a continuous barrier around theentire fence 80 using a plurality of fastening devices, such as screws,nails or the like. However, the barrier strip 50 may be provided in theform of continuous coil which is rolled out along side the length offence 80. The barrier strip 50 includes a plurality of equidistantopenings 60 such that a stake 20 is inserted through each of theopenings 60 and the lower point 40 of each stake 20 is driven below theground surface 70. The equidistant openings 60 are spaced sufficientlyclose together to prevent a dog from crawling or tunneling through tothe opposite side of the fence 80. The openings 60 are spaced mostpreferably approximately 4 inches apart, and 2 inches from the end ofthe barrier strip 50. It is important to achieve a close spacing of thestakes 20 to achieve the desired protective barrier around the fence 80.

As best shown in FIGS. 1 and 2, the plurality of openings 60 that arecut through the barrier strip 50 are cut to match the cross sectionalshape of the stakes 20 such that the openings 60 serve as key holeswhich are dimensioned just slightly smaller than the stakes 20. Theclose tolerance between the key holes and the stakes 20 yield a tightand secure fit. The key holes serve as a means to securely fit thestakes in the barrier strip, but other means of securing the fit issatisfactory. The secure fit is important because the fit resists anyupward movement in the soil which force the stakes 20 upward and out ofthe soil, enabling the dog to dig downward and crawl between theremaining stakes 20. Also, the secure fit resists the lifting of a stake20 by a dog. Furthermore, as shown in FIG. 10 the secure fit allowsvertical adjustment of a stake 20 to install the underground fencebarrier 10 along a fence 80 on uneven terrain in which case a longerstake length is selected depending upon the distance the bottom of thefence is from the ground.

As shown in FIGS. 8 and 9 the plurality of stakes 20 anchor the barrierstrip 50 to the ground 70 surface. The stakes 20, barrier strip 50, andfence 80 are coplanar to each other. As shown in FIGS. 3, 6, and 7 thestakes 20 may be concave shaped, but any shape is suitable so long as itmatches the key hole openings 60 in the barrier strip 50. The stakes 20could also be in the form of rods, nails, or the like. The stakes 20 areprovided in different lengths and selected depending upon the distancethe bottom of the fence 80 is from the ground 70 and also depending uponthe nature of the soil. A longer stake 20 is more appropriate if thesoil in a certain area is softer or more easily dug. A stake 20 isinserted into each of the openings 60 and driven into the ground 70 toprovide the underground barrier. Each stake 20 has an enlarged head 30which limits the downward passage of each stake 20 when it contacts thebarrier strip 50. Each stake 20 has a lower point 40 that extends intothe ground 70.

Stakes 20 of different variations are shown in FIGS. 3, 6, and 7. InFIG. 6, the stakes 20 are provided with a 90° bend near the head 30 tooffer a larger strike surface and lift point for removal. In FIG. 7,another variation of the stakes 30 include a stringing clip near thehead which serves as a working stop against the barrier strip 50 whendriving the stake 20. The stakes may be in the form of readily availablecurbing stakes because these are readily available in a hardware store.Typically, as shown in FIG. 3, an off-the-shelf curbing stake measures 1in wide×¼ in. thick×18 in. in length, and the key hole openings 60 inthe barrier strip 50 are cut to match the cross sectional shape of thecurbing stake.

Another embodiment of the present invention includes the method ofconstructing the underground barrier device 10. In use, it is intendedthat the device be constructed of readily available hardware componentssuch that it can be installed as a do-it-yourself type assembly. As bestshown in FIGS. 8, 9, and 10, the method of using the present inventionincludes the steps of positioning a barrier strip section as close aspossible to the existing fence. A stake is inserted through the key holeopenings at the ends of the barrier strip section and driven into theground. The remaining stakes are then inserted through the remains keyhole openings in the barrier strip and driven into the ground. Anappropriate stake length is selected based on the nature of the soil,the dog's ability to dig a tunnel, and the nature of the terrain. Longerstakes are used where there are soft soils easy to dig, dogs thatpossess superior tunneling ability, and uneven terrain which creates agap 90 between the bottom of the fence and the ground.

The underground fence barrier may be supplied in kit form, with aplurality of barrier strip 50 sections and stakes 20. The barrier strip50 may be provided in the form of a continuous coil that is rolled outalong the edge of the fence. The stakes may be provided in differentvariations as shown in FIGS. 3, 6, and 7. The kit will also contain aset of installation instructions.

It can be appreciated that the embodiments described above areillustrative of just a few of the numerous variations of arrangements ofthe disclosed elements used to carry out the disclosed invention.Moreover, while the invention has been particularly shown, described andillustrated in detail with reference to preferred embodiments andmodifications thereof, it should be understood that the foregoing andother modifications are exemplary only, and that equivalent changes inform and detail may be made without departing from the true spirit andscope of the invention as claimed, except as precluded by the prior art.

1. An underground fence barrier to prevent dogs from digging under anexisting fence comprising: a horizontal barrier strip near the bottomedge of existing fence; a plurality of openings in said strip; aplurality of stakes, said stakes being vertically oriented and coplanarwith respect to existing fence and said barrier whereby one stake passesthrough each opening in said strip, and each of said stakes having alower point driven below a ground surface.
 2. The underground fencebarrier of claim 1 wherein said horizontal barrier strip is held to theground by a plurality of stakes.
 3. The underground fence barrier ofclaim 2 wherein stakes of different length are used along saidhorizontal barrier strip.
 4. The underground fence barrier of claim 1wherein said openings are keyed to the cross sectional shape of saidstakes.
 5. A method for preventing dogs from digging under an existingfence comprising: attaching a a horizontal barrier strip near the bottomedge of existing fence; inserting a stake through each said opening insaid strip; driving said stake into said ground below said groundsurface whereby an underground barrier is formed which provides abarrier to any dog attempting to dig under the fence; and verticallyadjusting the stakes to cover any gaps between the fence and the ground.6. A underground fence barrier kit to prevent dogs from digging under anexisting fence comprising: a horizontal barrier strip with a pluralityof openings; a plurality of stakes; and a set of installationinstructions.